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Test utility methods encapsulate reusable test logic, enhancing modularity and maintainability in test suites. They help reduce duplication, simplify maintenance, and promote consistency across codebases. However, their characteristics and usage patterns are largely unexplored. We conduct a large-scale empirical study analyzing test utilities from 20 open-source projects to understand their prevalence, organization, frequency of use, and purposes. We find 84,197 utilities across the projects, averaging one utility for every three test methods in half of the projects. Most utilities are helper methods (88.9%) rather than life-cycle methods, with setup methods encapsulating test initialization (53.3%) and clean-up (30.8%). Notably, 58.4% have public visibility. Most tests (76%) utilize at least one utility, with over half (56%) shared across multiple tests. These findings provide new insights into how developers structure and reuse test logic, providing a basis for improving test organization and maintainability.